drivers/infiniband/ulp/srp/ib_srp.h

   1 /*
   2  * Copyright (c) 2005 Cisco Systems.  All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #ifndef IB_SRP_H
  34 #define IB_SRP_H
  35
  36 #include <linux/types.h>
  37 #include <linux/list.h>
  38 #include <linux/mutex.h>
  39 #include <linux/scatterlist.h>
  40
  41 #include <scsi/scsi_host.h>
  42 #include <scsi/scsi_cmnd.h>
  43
  44 #include <rdma/ib_verbs.h>
  45 #include <rdma/ib_sa.h>
  46 #include <rdma/ib_cm.h>
  47 #include <rdma/ib_fmr_pool.h>
  48
  49 enum {
  50         SRP_PATH_REC_TIMEOUT_MS = 1000,
  51         SRP_ABORT_TIMEOUT_MS    = 5000,
  52
  53         SRP_PORT_REDIRECT       = 1,
  54         SRP_DLID_REDIRECT       = 2,
  55         SRP_STALE_CONN          = 3,
  56
  57         SRP_DEF_SG_TABLESIZE    = 12,
  58
  59         SRP_DEFAULT_QUEUE_SIZE  = 1 << 6,
  60         SRP_RSP_SQ_SIZE         = 1,
  61         SRP_TSK_MGMT_SQ_SIZE    = 1,
  62         SRP_DEFAULT_CMD_SQ_SIZE = SRP_DEFAULT_QUEUE_SIZE - SRP_RSP_SQ_SIZE -
  63                                   SRP_TSK_MGMT_SQ_SIZE,
  64
  65         SRP_TAG_NO_REQ          = ~0U,
  66         SRP_TAG_TSK_MGMT        = 1U << 31,
  67
  68         SRP_MAX_PAGES_PER_MR    = 512,
  69
  70         LOCAL_INV_WR_ID_MASK    = 1,
  71         FAST_REG_WR_ID_MASK     = 2,
  72
  73         SRP_LAST_WR_ID          = 0xfffffffcU,
  74 };
  75
  76 enum srp_target_state {
  77         SRP_TARGET_SCANNING,
  78         SRP_TARGET_LIVE,
  79         SRP_TARGET_REMOVED,
  80 };
  81
  82 enum srp_iu_type {
  83         SRP_IU_CMD,
  84         SRP_IU_TSK_MGMT,
  85         SRP_IU_RSP,
  86 };
  87
  88 /*
  89  * @mr_page_mask: HCA memory registration page mask.
  90  * @mr_page_size: HCA memory registration page size.
  91  * @mr_max_size: Maximum size in bytes of a single FMR / FR registration
  92  *   request.
  93  */
  94 struct srp_device {
  95         struct list_head        dev_list;
  96         struct ib_device       *dev;
  97         struct ib_pd           *pd;
  98         struct ib_mr           *global_mr;
  99         u64                     mr_page_mask;
 100         int                     mr_page_size;
 101         int                     mr_max_size;
 102         int                     max_pages_per_mr;
 103         bool                    has_fmr;
 104         bool                    has_fr;
 105         bool                    use_fmr;
 106         bool                    use_fast_reg;
 107 };
 108
 109 struct srp_host {
 110         struct srp_device      *srp_dev;
 111         u8                      port;
 112         struct device           dev;
 113         struct list_head        target_list;
 114         spinlock_t              target_lock;
 115         struct completion       released;
 116         struct list_head        list;
 117         struct mutex            add_target_mutex;
 118 };
 119
 120 struct srp_request {
 121         struct scsi_cmnd       *scmnd;
 122         struct srp_iu          *cmd;
 123         union {
 124                 struct ib_pool_fmr **fmr_list;
 125                 struct srp_fr_desc **fr_list;
 126         };
 127         u64                    *map_page;
 128         struct srp_direct_buf  *indirect_desc;
 129         dma_addr_t              indirect_dma_addr;
 130         short                   nmdesc;
 131 };
 132
 133 /**
 134  * struct srp_rdma_ch
 135  * @comp_vector: Completion vector used by this RDMA channel.
 136  */
 137 struct srp_rdma_ch {
 138         /* These are RW in the hot path, and commonly used together */
 139         struct list_head        free_tx;
 140         spinlock_t              lock;
 141         s32                     req_lim;
 142
 143         /* These are read-only in the hot path */
 144         struct srp_target_port *target ____cacheline_aligned_in_smp;
 145         struct ib_cq           *send_cq;
 146         struct ib_cq           *recv_cq;
 147         struct ib_qp           *qp;
 148         union {
 149                 struct ib_fmr_pool     *fmr_pool;
 150                 struct srp_fr_pool     *fr_pool;
 151         };
 152
 153         /* Everything above this point is used in the hot path of
 154          * command processing. Try to keep them packed into cachelines.
 155          */
 156
 157         struct completion       done;
 158         int                     status;
 159
 160         struct ib_sa_path_rec   path;
 161         struct ib_sa_query     *path_query;
 162         int                     path_query_id;
 163
 164         struct ib_cm_id        *cm_id;
 165         struct srp_iu         **tx_ring;
 166         struct srp_iu         **rx_ring;
 167         struct srp_request     *req_ring;
 168         int                     max_ti_iu_len;
 169         int                     comp_vector;
 170
 171         struct completion       tsk_mgmt_done;
 172         u8                      tsk_mgmt_status;
 173         bool                    connected;
 174 };
 175
 176 /**
 177  * struct srp_target_port
 178  * @comp_vector: Completion vector used by the first RDMA channel created for
 179  *   this target port.
 180  */
 181 struct srp_target_port {
 182         /* read and written in the hot path */
 183         spinlock_t              lock;
 184
 185         /* read only in the hot path */
 186         struct ib_mr            *global_mr;
 187         struct srp_rdma_ch      *ch;
 188         u32                     ch_count;
 189         u32                     lkey;
 190         enum srp_target_state   state;
 191         unsigned int            max_iu_len;
 192         unsigned int            cmd_sg_cnt;
 193         unsigned int            indirect_size;
 194         bool                    allow_ext_sg;
 195
 196         /* other member variables */
 197         union ib_gid            sgid;
 198         __be64                  id_ext;
 199         __be64                  ioc_guid;
 200         __be64                  service_id;
 201         __be64                  initiator_ext;
 202         u16                     io_class;
 203         struct srp_host        *srp_host;
 204         struct Scsi_Host       *scsi_host;
 205         struct srp_rport       *rport;
 206         char                    target_name[32];
 207         unsigned int            scsi_id;
 208         unsigned int            sg_tablesize;
 209         int                     queue_size;
 210         int                     req_ring_size;
 211         int                     comp_vector;
 212         int                     tl_retry_count;
 213
 214         union ib_gid            orig_dgid;
 215         __be16                  pkey;
 216
 217         u32                     rq_tmo_jiffies;
 218
 219         int                     zero_req_lim;
 220
 221         struct work_struct      tl_err_work;
 222         struct work_struct      remove_work;
 223
 224         struct list_head        list;
 225         bool                    qp_in_error;
 226 };
 227
 228 struct srp_iu {
 229         struct list_head        list;
 230         u64                     dma;
 231         void                   *buf;
 232         size_t                  size;
 233         enum dma_data_direction direction;
 234 };
 235
 236 /**
 237  * struct srp_fr_desc - fast registration work request arguments
 238  * @entry: Entry in srp_fr_pool.free_list.
 239  * @mr:    Memory region.
 240  * @frpl:  Fast registration page list.
 241  */
 242 struct srp_fr_desc {
 243         struct list_head                entry;
 244         struct ib_mr                    *mr;
 245 };
 246
 247 /**
 248  * struct srp_fr_pool - pool of fast registration descriptors
 249  *
 250  * An entry is available for allocation if and only if it occurs in @free_list.
 251  *
 252  * @size:      Number of descriptors in this pool.
 253  * @max_page_list_len: Maximum fast registration work request page list length.
 254  * @lock:      Protects free_list.
 255  * @free_list: List of free descriptors.
 256  * @desc:      Fast registration descriptor pool.
 257  */
 258 struct srp_fr_pool {
 259         int                     size;
 260         int                     max_page_list_len;
 261         spinlock_t              lock;
 262         struct list_head        free_list;
 263         struct srp_fr_desc      desc[0];
 264 };
 265
 266 /**
 267  * struct srp_map_state - per-request DMA memory mapping state
 268  * @desc:           Pointer to the element of the SRP buffer descriptor array
 269  *                  that is being filled in.
 270  * @pages:          Array with DMA addresses of pages being considered for
 271  *                  memory registration.
 272  * @base_dma_addr:  DMA address of the first page that has not yet been mapped.
 273  * @dma_len:        Number of bytes that will be registered with the next
 274  *                  FMR or FR memory registration call.
 275  * @total_len:      Total number of bytes in the sg-list being mapped.
 276  * @npages:         Number of page addresses in the pages[] array.
 277  * @nmdesc:         Number of FMR or FR memory descriptors used for mapping.
 278  * @ndesc:          Number of SRP buffer descriptors that have been filled in.
 279  */
 280 struct srp_map_state {
 281         union {
 282                 struct {
 283                         struct ib_pool_fmr **next;
 284                         struct ib_pool_fmr **end;
 285                 } fmr;
 286                 struct {
 287                         struct srp_fr_desc **next;
 288                         struct srp_fr_desc **end;
 289                 } fr;
 290                 struct {
 291                         void               **next;
 292                         void               **end;
 293                 } gen;
 294         };
 295         struct srp_direct_buf  *desc;
 296         union {
 297                 u64                     *pages;
 298                 struct scatterlist      *sg;
 299         };
 300         dma_addr_t              base_dma_addr;
 301         u32                     dma_len;
 302         u32                     total_len;
 303         union {
 304                 unsigned int    npages;
 305                 int             sg_nents;
 306         };
 307         unsigned int            nmdesc;
 308         unsigned int            ndesc;
 309 };
 310
 311 #endif /* IB_SRP_H */